What are the chances of having another autistic child?

My fiance's Son was just diagnosed having Pervasive Developmental Disorder, Not Otherwise Specified (PDD-NOS) The doctor told her if she had another child the next one could have autism. The doctor also said this only just going off her diagnosing her son with PDD-NOS... which makes us concerned in return, if we decide to have a child of our own.



What are the chances with a different father in the mix, for us to have an autistic child?



Does PDD-NOS mean that her son is infact autistic? Are the chances less likey that we would have an autistic child? Because its PDD-NOS?What are the chances of having another autistic child?
From what I know of genetics (and its very little) your fiance's son has a defect on his chromosome. This means that it came from either your fiance or her son's father, and the only way to know for sure is a look at her chromosomes. I would say, just mathematically, her chances of having another child with chromosomal defects would go down 50% with you, because she is not with the original father. However, I could be completely wrong, and its all in her genes, not the father's. Did you ask your doctor? He or she would know more about PDD-NOS than I do.

Ordinarily, you'd have a 1 in 1000 chance your child would have a form of autism, but I don't know how PDD-NOS would affect that. That's really a question for your doctor. Good luck!